Doppler profiles of H and D atoms from the reaction of O(1D) with HD and a 1:1 mixture of H-2 and D2 have been measured by a multiphoton ionization technique as well as by a laser-induced fluorescence technique with a vacuum-ultraviolet laser. Isotopic channel branching ratios of PHI(OD+H)/PHI(OH+D) are measured in the reaction of O(1D) + HD at average collision energies E(coll) = 3.4 and 2.4 kcal/mol. In O(1D) + HD, the translational energy released to the OD + H product is almost twice that released to the OH + D product. The measured branching ratios and translational energies suggest that the reaction proceeds via a short-lived complex formed by insertion.